Double Glazing Calculators
Free tools that turn your window count, style and frame material into a realistic 2026 price range in seconds.
Every calculator below works the same way. You pick the number of windows, the style and the frame material, and it returns a low to high price range plus a per-window average, built from our 2026 cost data. None of them ask for your phone number, and none of them hand your details to a salesperson. If you only want the headline figure, start with how much double glazing costs per window and then come back to fine-tune it.
uPVC Window Calculator
The default for most UK homes. Estimate fitted uPVC casement, sash and tilt and turn windows.
Casement Window Calculator
The cheapest, most common style. Price hinged casement windows in any frame material.
Sash Window Calculator
Price vertical sliding sash windows for Victorian and Georgian homes, in uPVC or timber.
Tilt and Turn Calculator
Dual-opening windows ideal for flats and upper floors, in uPVC or slim aluminium.
Bay Window Calculator
Projecting bay windows priced per bay, including the structural fitting work.
Bow Window Calculator
Curved bow windows priced per bow, by the number of sections, in any frame.
French Window Calculator
Postless double openings for windows and doors, with a clear full-width view.
Picture Window Calculator
Fixed, non-opening panes for light and a view. The cheapest style per opening.
Flush Casement Calculator
Sashes that close flush with the frame for a period look. A premium over standard casements.
Aluminium Window Calculator
Slim-frame aluminium windows for a modern look. Expect a 30 to 40% premium over uPVC.
Timber Window Calculator
Hardwood and softwood windows for period and conservation-area homes.
Door Cost Calculator
Front, French, patio and bifold doors, supply and fit, in uPVC, composite and aluminium.
Conservatory Glazing Calculator
Glass and polycarbonate conservatory roofs plus glazed side panels, priced per m².
Energy Savings Calculator
See how much A-rated double glazing could trim from your annual heating bill.
Repair Cost Calculator
Misted units, reseals, handles and hinges, with a repair-versus-replace comparison.
Which calculator should I use?
For most homes the uPVC window calculator or the casement window calculator is the right starting point, because an A-rated uPVC casement is the cheapest frame and suits the majority of UK properties. Pick the style that matches your home: a sash for a Victorian or Georgian house, a bay for a projecting front window, a tilt and turn for a flat, or a fixed picture window for light and a view. Period or conservation-area home? Use the timber calculator. Replacing doors as well? The door cost calculator covers front, French, patio and bifold doors, and the conservatory glazing calculator handles glass roofs and glazed sides. If a window has only misted rather than failed, the repair cost calculator weighs a fix against a full replacement. To sense-check whether the spend pays back, run the energy savings calculator. Each tool returns a range, not a single number, because real quotes vary with access, glass spec and your region.